You can't use the V5 from another car to register yours. You have a marlin not a Marina. People have just registered their kit car as the donor . A classic not long back was an MGBGT 1800 based NG registered as a Blue 1300 Anglia! If you get caught your pride and joy will probably be crushed. Some police are knowledgeable about kit cars and a Marlin looks nothing like a Marina. Get on the Marlin forum if you haven't already. As Abracada8raman said, be careful what you say on an open forum. Good luck.